This invention relates to a sanitary napkin which is formed from liquid-absorbent material and is worn for collection of menstrual fluids. More particularly, the sanitary napkin includes at least one elongated swellable sponge supported on a base layer of absorbent sheet material, and a cover layer of absorbent sheet material joined at its edge portions to the edge portions of said base layer of sheet material and extending about and covering the sponge. Optionally, additional elongate pads extend parallel to and adjacent to said sponge.
Sanitary napkins or pads which are worn externally by women for the collection of menstrual fluids must be of sufficient absorbency in order to function to collect fluids, but in order to increase the absorbency of prior art napkins, the napkins usually have been increased in bulk, either in thickness or in width, or both, in order to provide additional material for absorbing the liquids. The thick or wide napkins usually are uncomfortable to the wearer, and when the thick napkins are compressed during normal use by the wearer, the material of the napkin is less capable of absorbing and retaining the fluids. Additionally, sanitary napkins sometimes tend to become twisted or shifted out of proper position when in use, causing discomfort to the wearer and reducing the ability of the napkin to collect the fluids.
Various stiffeners, belts and adhesive strips have been used in the past in order to help sanitary napkins to retain their shape and to keep their position during use, but these features have not been completely effective in solving the above-listed problems.
In general, it is desirable to the wearer of a sanitary napkin to have the napkin of small width and thickness and of a shape that fits comfortably in the space available and yet have the napkin capable of absorbing and retaining a large amount of menstrual fluids.